Cell culture is a vital part of the biotechnology revolution, and is important in bringing many new and useful developments to society. During certain kinds of cell culture, in particular In Vitro Fertilization (IVF), the growth and viability of the cells is particularly sensitive to the environmental conditions during growth. Principal among these conditions are the temperature and CO2 which effect the pH level of the growth media, where it has been shown that even small changes in temperature and/or CO2 can adversely affect the pH levels which in turn can lead to lower chances of successful cell growth, and in the case of IVF, to a lack of success in final implantation and pregnancy. IVF generally helps couples who have difficulty conceiving, and even with the best technology, the chances for some couples successfully achieving pregnancy are low.
IVF laboratories generally grow cells in an incubator, which allows for the maintenance of a constant environment for the growing cells. The pH of growth media is frequently maintained in the incubator by controlling of the level of carbon dioxide gas which produces carbonic acid when dissolved in water. Accordingly, the more carbon dioxide present in the environment, the lower the pH of the media. Laboratories using IVF often have to remove the container of media and cells from the incubator to perform manipulations, and possibly to make measurements of characteristics such as temperature and pH within the growth media. This is undesirable because each time the cells are removed from the incubator there is a period of time in which the cells are exposed to an uncontrolled environment where they may experience changes of temperature, pH, and light, all of which affect the viability of the cells. Consequently, removal of the cells and media from the incubator removes the control of the pH provided by the regulated carbon dioxide levels in the incubator. And, if there is a problem with the carbon dioxide levels in the incubator, the pH of the media could change and threaten the viability of the cells.
Accordingly, there have been attempts to find ways to measure certain characteristics of the cells, such as pH and temperature, without having to remove the cells from the incubator. One such attempt includes obtaining an optical pH measurement via the use of dyes and/or color discs. However, while this method appears to be functional, it generally does not provide the accuracy required to adequately monitor and maintain the cells and media. This inability to accurately monitor and maintain the cells and media is undesirable because the viability of the cells and media may be negatively affected without the laboratory personnel being aware.